The ethene that's produced can be used for a feedstock and the remaining water is removed. Ethene is then reacted with steam at a high temperature and pressure in the presence of a catalyst to produce ethanol

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How is ethanonol for use in alcoholic drinks produced?

Fermentation

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What are the three stages of fermentation to produce ethanol?

1. Water and yeast are mixed with natural sugars at just above room temperature 2. Enzymes found in the yeast catalyse the formation of ethanol and carbon dioxide 3. The carbon dioxide can escape from the reaction vessel, but air can't enter it

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What is the word equation for the synthesis of ethanol?

Ethene + Steam -----> Ethanol

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What is the word equation for the fermentation of ethanol?

Glucose -----> Ethanol + Carbon dioxide

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When ethanol solution is manufactured by fermentation, how is the concentration limited?

1. The amount of sugar in the mixture 2. The fact that, above a certain temperature, the ethanol kills the yeast

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How can the concentration of ethanol be increased when the fermentation reaction is over?

Distillation

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What 3 things effect the optimum conditions needed for fermentation?

Temperature, pH, oxygen

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What does the term 'denatured' mean?

The shape is irreversibly changed

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What 2 things are used to produce ethanol using the biotechnology method?

Genetically modified E.coli bacteria, waste biomass

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Why do the E.coli bacteria used in the biotechnology method of producing ethanol have new genes introduced?

So that the bacteria digest all the sugars in the biomass and convert them to alcohol

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What is bioethanol used for?

Fuel

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What are the optimum conditions for the biotechnology process?

1. The temperature should remain 25-37°C 2. The optimum pH levels need to remain constant otherwise the enzyme will be denatured

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The presence of what function group cause the characteristic properties of carboxylic acids?

-COOH

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What is the name of the carboxylic acid HCOOH?

Methanoic acid

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What is the name of the carboxylic acid CH3COOH?

Ethanoic acid

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What type of acid is responsible for the taste of vinegar, the smell of sweaty socks and the taste of rancid butter?

Carboxylic

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Are carboxylic acids more or less reactive than acids like sulfuric acid, nitric acid and hydrochloric acid?

Carboxylic acids are weak therefore are less reactive

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When carboxylic acids react with metals, what is produced?

A salt and hydrogen

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When carboxylic acids react with carbonates, what is produced?

A salt, water and carbon dioxide

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When carboxylic acids are neutralised by alkalis, what is formed?

A salt and water

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What is produced when ethanoic acid and sodium react?

Sodium ethanoate + Hydrogen

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What is produced when ethanoic acid and sodium carbonate react?

Sodium ethanoate + Water + Carbon dioxide

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What is produced when ethanoic acid and sodium hydroxide react?

Sodium ethanoate+ Water

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What forms when carboxylic acids reacts with alcohols?

Esters

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The reaction of carboxylic acids and alcohols which results in the formation of esters is carried out in the presence of what type of catalyst?

Strong acid catalyst

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What have distinct smells which are responsible for the smells and flavours of fruits, are used in the manufacture of perfumes and food products and are also found in solvents and plasticizers?

Esters

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What is the word equation for the reaction of a carboxylic acid and an alcohol?

Carboxylic acid + Alcohol -----> Ester + Water

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What are fats the esters of?

Glycerol, fatty acids

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What are fats and oils?

Naturally occurring esters

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Animal fats are mostly saturated molecules.What type of bonds do they have and are the molecules reactive?

They have single carbon-carbon bonds and they are unreactive

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Vegetable oils are mostly unsaturated molecules. What type of bonds do they have and are the molecules reactive?

They have some double carbon-carbon bonds and they are reactive

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Fill in the gaps. Exothermic changes _______ energy and you can detect this energy because there is usually a temperature change. They release energy because the ______ have less energy that the ______ did.

Release, products, reactants

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Fill in the gaps. Endothermic changes are ____ common than exothermic changes and ______ energy so usually feel cold to touch. You can detect the energy change because the temperature usually ____.

Less, take in, falls

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In a chemical reaction, what must be broken in order to form new products?

The bonds in the reactants

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What is activation energy?

The energy needed to break bonds to start a reaction.

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Is breaking bonds an exo or endothermic process?

Endothermic

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Is making bonds an exo or endothermic process?

Exothermic

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Chemical reactions that absorb more energy to break the bonds in the reactants than is released when new bonds are made in the products are what type of change?

Endothermic

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Chemical reactions in which more energy is released when new bonds are made than was absorbed to break the old bonds are what type of energy change?

Exothermic

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What type of reaction is represented with a double-headed arrow?

Reversible

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Fill in the gaps. In a reversible reaction, the _______ can react together to produce the original _______.

Products, reactants

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If a reversible reaction is in a closed system and is left for long enough, what will it reach?

A state of dynamic equilibrium

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When a dynamic equilibrium is established, why don't the concentration of products (and reactants) change over time?

The forward and backward reactions happen at exactly the same time

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How does the Haber process convert atmospheric nitrogen to ammonia?

By reacting it with hydrogen from natural gas

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What is ammonia used to make?

Fertilisers, explosives, dyes, medicines and a variety of other essential chemicals

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What is a qualitative analysis?

Any method used to identify the chemicals in a substance

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What is a quantitative analysis?

Any method used to determine the amount of chemical in a substance

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What is chromatography used for?

To find out what unknown mixtures are made up of

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Why are substances separated as they move through the stationary phase in chromoatography?

They move at different speeds

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What is the solvent that's used to move the solution in chromatography called?

Mobile phase

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What is the medium that the solvent moves through in chromatography called?

Stationary phase

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What are the first four stages of paper chromatography?

1 Dissolve substance if solid in a solvent 2 Place spot of resulting solution on sheet of chromatography paper on pencil line 3 Place bottom edge of paper in solvent 4 Solvent rises up paper, dissolving spot, carrying it up the paper

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What is the last stage of paper chromatography?

The different chemicals in the mixture separate because their molecules have different sizes and properties

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What are three advantages of thin layer chromatography over paper chromatography?

1. Faster runs 2. More even movement of the mobile phase through the stationary phase 3. A choice of different absorbencies for the stationary phase

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What is the mobile phase in gas chromatography?

A carrier gas

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What is the stationary phase in gas chromatography?

A microscopic layer of liquid on an unreactive solid support

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In gas chromatography, what happens to a sample of a substance when it is injected into one end of the heated column?

It vaporises

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Why is gas chromatography able to separate the components in a mixture?

They have different solubilities

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What are three advantages of using gas chromatography over thin layer chromatography and paper chromatography?

1. Greater separating power 2. Ability to separate complex mixtures 3. Ability to produce quantitative data from very small samples of liquids, gases and volatile solids